Benzimidazole design,synthesis, and docking to build selective carbonic anhydrase VA inhibitors

The similarity of human carbonic anhydrase (CA) active sites makes it difficult to design selective inhibitors for one or several CA isoforms that are drug targets. Here we synthesize a series of compounds that are based on 5-[2-(benzimidazol-1-yl)acetyl]-2-chloro-benzenesulfonamide (1a) which demonstrated picomolar binding affinity and significant selectivity for CA isoform five A (VA), and explain the structural influence of inhibitor functional groups to the binding affinity and selectivity. A series of chloro-substituted benzenesulfonamides bearing a heterocyclic tail, together with molecular docking, was used to build inhibitors that explore substituent influence on the binding affinity to the CA VA isoform.     

Specificity of synexin-induced chromaffin granule aggregation

Preparations of synexin (1) exhibit a self-interaction in the absence of chromaffin granules as evidenced by an increase in absorbance at the wave-length used for observing granule aggregation (2). We incorporated this observation into a new formula for calculating the synexin-induced chromaffin granule aggregation. According to this amended analysis, synexin-induced aggregation is specific for chromaffin granules or their membranes. Treatment of intact chromaffin granuleswith trypsin or pronase renders the granules unresponsive to synexin.     

<Emphasis Type="Italic">Scolytus multistriatus</Emphasis> associated with Dutch elm disease on the island of Gotland: phenology and communities of vectored fungi

Scolytus multistriatus Marsham, the smaller European elm bark beetle, is a vector for Dutch elm disease (DED) that in the year 2005 invaded the island of Gotland (Sweden). The island possesses the largest population of elm (mainly Ulmus minor Mill.) in northern Europe. The aim of this study was to monitor flying periods of S. multistriatus during three consecutive years and by using high-throughput sequencing to assess communities of vectored fungi. Sampling of the beetles was carried out at two different sites in Gotland in 2012, 2013, and 2014. In total, 50 pheromone traps were placed at each site and checked weekly during June-August each year. From all sites and years, 177 beetles were trapped. Among these, 6.2 % were trapped in June, 76.8 % in July, and 16.9 % in August (difference significant at p<0.007). Sequencing of ITS rDNA from the beetles revealed the presence of 1589 fungal taxa, among which virulent DED pathogen Ophiostoma novo-ulmi Brasier was the second most common species (9.0 % of all fungal sequences). O. ulmi Buisman, the less virulent DED pathogen, was also detected but only in a single beetle, which was sampled in 2012 (0.04 % of sequences). There were 13.0 % of the beetles infested with O. novo-ulmi in 2012, 4.0 % in 2013, and 27.7 % in 2014. O. novo-ulmi comprised 0.8 % of fungal sequences in 2012, 0.002 % in 2013, and 8.2 % in 2014. The study showed that the proportion of S. multistriatus vectoring O. novo-ulmi has increased in recent years.     

The ectomycorrhizal community of conifer stands on peat soils 12 years after fertilization with wood ash

We studied long-term effects of fertilization with wood ash on biomass, vitality and mycorrhizal colonization of fine roots in three conifer forest stands growing in Vacciniosa turf. mel. (V), Myrtillosa turf. mel. (M) and Myrtillosa turf. mel./Caricoso-phragmitosa (MC) forest types on peat soils. Fertilization trials amounting 5 kg/m² of wood ash were established 12 years prior to this study. A total of 63 soil samples with roots were collected and analysed. Ectomycorrhizal (ECM) fungi in roots were identified by morphotyping and sequencing of the fungal internal transcribed spacer (ITS) region. In all forest types, fine root biomass was higher in fertilized plots than in control plots. In M forest type, proportion of living fine roots was greater in fertilized plots than in control plots, while in V and MC, the result was opposite. Fifty ECM species were identified, of which eight were common to both fertilized and control plots. Species richness and Shannon diversity index were generally higher in fertilized plots than in control plots. The most common species in fertilized plots were Amphinema byssoides (17.8 %) and Tuber cf. anniae (12.2 %), while in control plots, it was Tylospora asterophora (18.5 %) and Lactarius tabidus (20.3 %). Our results showed that forest fertilization with wood ash has long-lasting effect on diversity and composition of ECM fungal communities.